   Chapter 4, Problem 47P

Chapter
Section
Textbook Problem

To meet a U.S. Postal Service requirement, employees’ footwear must have a coefficient of static friction of 0.500 or more on a specified tile surface. A typical athletic shoe has a coefficient of 0.800. In an emergency, what is the minimum time interval in which a person starting from rest can move 3.00 in on the tile surface if she is wearing (a) footwear meeting the Postal Service minimum and (b) a typical athletic shoe?

(a)

To determine
The minimum time interval when the employee wears footwear.

Explanation

Given Info: Co-efficient of static friction ( μs ) is 0.500. The distance to be covered is 3.00 m.

From Newton’s equation, the distance is,

s=ut+12at2 (I)

• u is the initial velocity.
• t is the time interval.
• a is the acceleration.

The normal force balances the weight. The forward force equals the maximum static friction.

N=mg (II)

(Fs)max=ma (III)

The co-efficient of static friction is,

μs=FkN

Divide Equation (III) by (II) and substitute in the above equation.

μs=ag

On Re-arranging,

a=μsg (IV)

Substitute Equation (IV) in (I)

(b)

To determine
The minimum time interval when the employee wears an athlete shoe.

Still sussing out bartleby?

Check out a sample textbook solution.

See a sample solution

The Solution to Your Study Problems

Bartleby provides explanations to thousands of textbook problems written by our experts, many with advanced degrees!

Get Started

How may our senses be enhanced?

An Introduction to Physical Science

Which chemical processes take place during digestion?

Introduction to General, Organic and Biochemistry

Name the following phenols.

Organic And Biological Chemistry 